What is the Apolipoprotein E Protein?

November 12, 2012

The apolipoprotein E protein is created by the APOE gene. This gene also goes by other names, such as Apo-E, Apolipoproteins E, and APOE_HUMAN.

What is the APOE Gene For?

The APOE gene basically provides instructions on how to make the apolipoprotein E protein, which combines with bodily fats to create special molecules known as lipoproteins. These lipoproteins are then put in charge for packaging fats like cholesterol and sending them into the bloodstream.

Apolipoprotein E also happens to play a big part in the life of lipoproteins with very low density, or VLDLs. VLDLs are basically in charge of getting rid of the extra cholesterol in the blood and sending it to the liver where it can be processed. Maintaining normal cholesterol levels happens to be very vital in order to prevent blood vessel and heart problems, like strokes and heart attacks.

What Happens When Changes are Made in This Gene?

Well, for starters, some changes made in the APOE gene could increase a person’s overall risk for Alzheimer’s disease. Those who get an APOE e4 allele copy, for example, get a slightly higher risk for it, while those who get two allele copies get an even higher risk for it. This allele is sometimes also associated to early onsets of memory loss.

Although nobody really knows for sure how this allele is connected to the risk for Alzheimer’s disease, researchers have come to find that it is connected to various protein clumps inside the affected people’s brain tissues. A buildup of amyloid plaques and beta peptide might kill the neurons and this disorder’s progressive symptoms and signs, though.

It would be vital to remember that people with this allele only get a higher risk for Alzheimer’s disease, though. It doesn’t mean that they will actually get the disease in the end. So, not everybody who has Alzheimer’s disease actually has this allele nor does everybody with this allele end up with the disease.

There are other disorders related to the apolipoprotein E gene, as well.For example, APOE alleles are known to influence the overall risk for heart diseases. So, people with an APOE e4 allele copy actually have higher risks for atherosclerosis, a condition that could increase their risk for strokes and heart attacks, as well. APOE e2 alleles, on the other hand, are known to increase a person’s risks for hyperlipoproteinemia type III, a rare condition that involves high cholesterol levels and fatty materials that could eventually result in atherosclerosis.

Some changes in the apolipoprotein E gene are also known to increase people’s overall risk for age-related macular degeneration. This eye disease happens to be the most common cause of global vision loss in senior citizens. Having a single APOE e4 allele could help protect people against this condition, though, or at least delay vision loss altogether. However, more research is still required to know if this is actually true.